Well bore casing fluid flow control apparatus



June 9, 1964 K. F. WENTS ETAL 3,136,368

WELL BORE CASING FLUID FLOW CONTROL APPARATUS 2 Sheets-Sheet 1 Filed Feb. 27, 1962 x mm 5 M WT m N v r I a W 4 M L E T EHWM wmwKK mm a 3 Q Q Q 9 June 9, 1964 3,136,368

WELL BORE CASING FLUID FLOW CONTROL APPARATUS K. F. WENTS ETAL 2 Sheets-Sheet 2 Filed Feb. 27, 1962 UNA/M Wm iii h mm mm mm nw &

K/vA/En/ E g INVENTORS PVZ-vvrs KURT LEUTWYLER BY WW 47'70PA/EY.

United States Patent 3,136,368 WELL BQRE CASING FLUID FLOW CONTROL APPARATUS Kenneth F. Wents, La Mirada, and Kurt Leutwyler, Whittier, Calih, assignors to Baker Oil Tools, Inc., Los Angelcs, Calif., a corporation of California Filed Feb. 27, 1962, Ser. No. 175,933 16 Claims. (Cl. 166-224) The present invention relates to subsurface well apparatus, and more particularly to apparatus adapted to be incorporated in a casing string, or similar conduit string, for the purpose of controlling the flow of fluid therein.

Valve devices have been incorporated in well casing, and similar conduit strings, to control the flow of well bore fluid into the casing as it is lowered in the well bore. As disclosed in U.S. Patent Re. 24,659, a throttling or elastic diaphragm orifice device is proposed for this purpose, the size of the orifice automatically increasing as the pressure differential acting thereon increases, as the result of running the casing in the well bore, to allow the casing to fill at a faster rate. Since the elastic diaphragm or disc can also be employed as a valve seat against which a back pressure valve element, such as a ball, can seat, the diaphragm has been made of ample thickness to Withstand relatively high back pressures. A

As the casing is run in'the well bore, the diaphragm bends upwardly under the action of the fluid pressure, increasing the orifice size. However, the maximum diameter to which the orifice can be enlarged is limited by the thickness of the diaphragm. With a thick diaphragm and its attendant limitation in the size to which the orifice can be enlarged, it becomes more subject to plugging while the casing is being run in the well bore. A thick diaphragm also requires greater pressure to pump a back pressure ball through its expandible orifice, the ball ejecting from the diaphragm and striking a substantial impact blow on the ball holding or retainer elements therebelow.

The maximum size to which the orifice can be expanded is capable of increase by reducing the thickness of the diaphragm, but such thinner member is incapable of subsequently withstanding sufficiently high back pressures when engaged by a ball valve element, or the like.

Accordingly, it isan object of the present invention to provide apparatus adapted to form part of a conduit string and embodying an elastic diaphragm orifice having substantialily less thickness than heretofore necessary to permit the orifice to increase to a greater diameter while running the casing string through the fluid in the well bore, but which is still capable of coacting with a back pressure valve element and withstanding comparatively high back pressures.

Another object of the invention is to provide apparatus of the character indicated which allows a valve element to be pumped downwardly through its orifice with lesser pressure, to reduce the impact load or blow of the valve element on the valve element holding parts therebelow, the valve element being movable upwardly into engagement with the diaphragm to withstand comparatively high back pressures.

A further object of the invention is to provide a back pressure valve apparatus adapted to be incorporated in a conduit string, such as a string of Well casing, to be lowered in a well bore, the apparatus embodying a diaphragm against which a back pressure valve element can seat, the diaphragm being capable of deflecting downwardly to increase the diameter of the passage therethrough, thereby facilitating downward flow of fluid through the conduit string, the diaphragm also being Patented June 9, 1964 capable of withstanding high back pressures when engaged by'the upwardly seating back pressure valve element.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part'of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of theinvention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a longitudinal section through an apparatus embodying the invention, with parts in one relative position;

FIG. 2 is a cross-section taken along the line 22 on FIG. 1;

FIG. 3 is a partial longitudinal section similar to FIG. 1, illustrating'the diaphragm of the apparatus deflected in an upward direction as a result of lowering the apparatus through fluid in the well bore;

FIG. 4 is a view similar to FIG. 1 illustrating a valve element being pumped downwardly through the diaphragm of the apparatus;

FIG. 5 is a view similar to FIG. 1 illustrating the valve element shifted upwardly into engagement with its companion diaphragm valve seat.

The apparatus A illustrated in the drawings is adapted to be incorporated in a string of casing B, which is to be lowered through fluid in a well bore, and through which other fluids can be pumped, as, for example, cement slurry used in cementing the well casing in the well bore. The specific apparatus illustrated is inserted in the casing string, being secured at a location where adjacent casing sections 10, 11 are coupled together.v As disclosed, an upper casing section 10 has its lower'pin 12 threaded into the upper portion of a coupling 13, the lower portion of the coupling being threaded onto the upper threaded pin 14 of a lower casing section or tubular member 11. The valve apparatus A is secured to the string of casing B between the upper and lower casing sections 10, 11.

As disclosed, the valve apparatus includes a valve body 15 comprising an upper head 16 having an inwardly extending transverse wall 17 surrounding a central passage 18 through the head. An outwardly directed flange 19 extends from the head and is externally threaded to threadedly mesh with the internal threads of the coupling 7 13. A skirt 20 integral with the head and depending therefrom receives an upper portion 21 of a lower body member 22, which is piloted upwardly thereinto, the two parts of the body member being secured together by generally radial coupling pins 23. The lower body member 22 includes circumferentially spaced downwardly extending stop and retainer elements in the form of legs 24, which terminate in inwardly directed retainer feet or lugs 25 adapted to be engaged by a valve element 26, such as a ball, which may either be initially incorporated in the apparatus A, or which may be pumped downwardly through the casing, as described hereinbelow.

A pliant, elastic diaphragm 27 is incorporated in the valve apparatus, the diaphragm including an outer base portion 28 and an inner flexible central portion 29 surrounding a central orifice 30. The central portion 29 extends across the central passageway 18 through the valve head 16, the upper portion of the diaphragm base engaging the lower side 31 of the transverse body wall 17. The diaphragm 27 is held upwardly against the transverse wall 17 by the upper end 32 of the lower valve body section 22, the diaphragm being held between the upper and lower body sections 16, 22.

It is to be noted that the transverse wall 17 extends inwardly towards the axis of the apparatus to a much greater extent than the upper portion 32 of the lower body section 22. In fact, the upper inner portion33 of the lower section is beveled or inclined in an upward and outward direction to permit the diaphragm 27 to deflect in a downward direction away from the transverse wall 17. How ever, upward movement of the diaphragm is limited by engagement of its upper surface 34 with the underside of the transverse wall 17. When so engaged, the central portion 29 of the diaphragm candeflect upwardly into the central passage 18. of the wall, increasing the size of the orifice opening 30.

The diaphragm 27 and its central portion 2h can be made comparatively thin, as compared to prior devices, so that the central portion of the diaphragm can deflect upwardly and provide a much greater maximum orifice opening than in prior devices. Despite such thinness, however, the diaphragm is still capable of being engaged by an upwardly seating valve element 26 to withstand substantial back pressures. The diaphragm has flat, disclike reinforcing segments 35 incorporated therein, these segments being disposed around the diaphragm and received within comparatively narrow but radially extending diaphragm grooves 36. The portion 37 of the diaphragm above the flat reinforced segments 35 terminates short of the inner wall 38 of the skirt 2% to facilitate pivoting of the segments during use of the apparatus, as described hereinbelow. The diaphragm segments 35 extend inwardly at least to a slight extent across the central passage 18 through the transverse wall 17.

As described above, the threaded flange 1@ is adapted to threadedly mesh with the internal threads of the coupling 13. The outside diameter of the skirt 2% is less than the inside diameter of the casing section 11, so that the skirt can extend into the upper portion of the latter. In assembling the valve apparatus in the casing, the coupling 13 is first threaded onto the upper pin end 14 of the lower casing section 11. A metal back-upring 4i) is placed on sees the upper end of the lower casing section or pin 14, followed by a rubber or rubber-like seal 41, the upper surface of which is engageable with the lower side of the body flange 19; This lower portion of this seal has a downward and outwardly inclined inner surface 42 engaging a companion inclined surface 43 on the back-up ring. The valve apparatus A is inserted into the upper end of the coupling 13 and a suitable wrench (not shown) inserted in radial recesses 44 in the upper portion of the body head 16 to turn the valve body 15 as a unit and thread its flange 19 downwardly in the coupling into engagement with the seal ring 41, forcing the latter against the back-up ring 40, the inclined surfaces 42, 43 urging the seal ring outwardly into the coupling threads. The seal ring 41 bears firmly against the head 16 and its flange 19 and against the back-up ring 40, also filling the thread spaces in the coupling 13, in order to prevent fluid leakage around the valve head and between its valve head and the coupling. The upper casing section 19, or other tubular member, is then threaded into the upper portion of the coupling 13 and tightened against the head flange 19, thereby insuring retention of the valve apparatus A in its appropriate location within the string of well casing B.

The casing string B is lowered through the fluid in the well bore. During such lowering movement, the well bore fluid flows upwardly through the diaphragm orifice 30, the flexible central portion 29 of the diaphragm deflecting upwardly. When the casing .is being lowered through the fluid in the well bore at a rapid rate, the central portion may deflect upwardly to a maximum extent, such as illustrated in FIG. 3, providing a greatly enlarged orifice diameter and thereby allowing the fluid to flow upwardly into the string of easing B at a rapid rate, avoiding the building up of excessive pressures in the well bore fluid. The size of the orifice 30 will vary depending upon the pressure differential generated below the apparatus, as the result of lowering the string of casing through the fluid in the well bore, automatically adjusting itself to the pressure differential conditions. Inas much as the central portion 29 of the diaphragm or disc 27 is relatively thin, such portion can deflect upwardly and provide a much greater maximum size of orifice than was heretofore possible.

When the casing B'has been run to its appropriate location ordepth in the well bore, circulating fluid may be pumped down the casing string. This fluid will deflect the diaphragm 2'7 downwardly to facilitate the flow of fluid therethrough. If the pressure above the diaphragm increases sufficiently, the reinforcing segments 35 may pivot in a downward direction about their outer ends, so

as to facilitate the increase in diameter of the orifice 30 and, therefore, allow fluid to flow downwardly with less restraint through the apparatus A. When the fluid pressure diminishes or is relieved, the inherent elasticity of the diaphragm 27 will return the segments 35 and the diaphragm itself to its original position disclosed in FIG. 1. Cement slurry, or the like, may be pumped down the string of easing Bfor the purpose of cementing it in the well bore.

To prevent return flow of the cement slurry into the casing string, a valve element, such as the ball 26, may be pumped down the casing string B, this valve element preferably having a diameter but slightly less than the diameter of the central passage 1-3 through the valve body head 16 and slightly greater than the inner diameter across the reinforcing segments 35. This ball valve element will pass into the central head passage 18, engaging the diaphragm'Zl', the pressure shifting the diaphragm downwardly and the ball stretching its central portion 29 downwardly and outwardly. The ball may also engage the inner portions of the segments 35 and willtilt or rock the segments in a downward direction, such as disclosed in FIG. 4, until the effective internal diameter across the segments is greater than that of the ball, whereupon the ball is pumped through the greatly enlarged orifice or central passage 30 through the diaphragm and into the lower body section 22, the ball coming to rest upon the inwardly projecting retainer feet or lugs 25. After the ball passes through the diaphragm or disc 27, the latter will return inherently to its initial position, with the base portion 28 of the diaphragm engaging the transverse wall 17 of the body head. At this time, the ball 26 is spaced below the diaphragm, resting upon the retaining lugs 25, as shown inbrokenlines in FIG. 4.

Cement slurry, or the like, can now be pumped down the casing string B, flowing through the central head passage 18 and through the diaphragm orifice 30, passing around the ball 26 and between the retainer legs 24 and feet 25 into the lower casing section 11, discharging from the casing into the well bore. If the pressure of the fluid being pumped downwardly through the well casing increases sufficiently, the diaphragm 27 can deflect in a downward direction to enlarge the size of the orifice and thereby facilitate the flow of the fluid, such as cement slurry, through the apparatus.

When the desired quantity of cement slurry has been ejected from the casing, the pressure in the well casing is relieved, whereupon the ball valve element 26 will move back upwardly into engagement with the disc or diaphragm 27, closing its central orifice 36) and preventing return flow of fluid therethrough and back into the casing section 16 thereabove (FIG. 5). The ball 26 engages the diaphragm 27 and cannot pass back upwardly therethrough, since the base portion 28 of the diaphragm engages the transverse walll7, and also due to the fact that the reinforcing segments are bearing upon the upper part 37 of the base portion and extend partially across the central passage 18 through the valve head 16, the internal diameter of the reinforcing segments 35, when in the position illustrated in FIG. 5, being less than the diameter of the ball 26. Thus, the rubber, or other pliant, elastic material, of which the diaphragm 27 is madeis reinforced or backed up by the segments 35, which, in turn, bear through the upper portion 37 of the diaphragm against the transverse wall 17. The upward thrust of the ball is transmitted through the rubber to the segments, and through the upper base portion 37 of the latter to the transverse wall 17.

The ball 26, the rubber or rubber-like diaphragm 27, and reinforcing segment arrangement is capable of withstanding very high back pressures without fear of the ball 26 being pumped back up through the diaphragm orifice 30 and into the casing string thereabove. Despite its ability to withstand high back pressures, the reinforcing segments 35 and the diaphragm 27 still can be shifted downwardly to the position indicated in FIG. 4 at substantially low pressures, to facilitate the downward passage of the ball therethrough into the lower retainer portion 22 of the body 15, and also to facilitate downward pumping of fluids or fluent materials through the apparatus. With the valve apparatus A illustrated and described, the diaphragm 27, and particularly its central portion 29, can be made comparatively thin and capable of deflecting upwardly to provide a much larger maximum orifice opening 30 than was heretofore available. Because of the thinner diaphragm 27 and the manner in which the segments 35 coact therewith, and in view of the provision of lesser backing at the underside of the diaphragm than is provided by the transverse wall 17 thereabove, the orifice size can be increased to a considerable extent with the exertion of lesser pressures thereon, thereby allowing the ball valve element 26 to be pumped therethrough with lesser pressure and resulting in its engaging the lower lugs 25 with a much lesser impact blow than would be presented by the necessity for pumping the ball through the diaphragm at a much higher pressure, due to an increased thickness of the diaphragm. Despite its substantial reduction in thickness, the diaphragm 27 still is capable of being engaged by the ball valve element 26 to withstand comparatively high back pressures, because of its coaction with .the reinforcing and other elements of the apparatus.

Although the apparatus has been specifically disclosed in connection with the automatic filling of a well casing and the subsequent pumping of a ball valve element 26, or the like, therethrough, to function as a back pressure valve, it can, if desired, operate only as a back pressure valve device. Thus, the ball valve element 26 can initially be disposed in the lower section 22 of the valve body 15, resting upon the retainer feet or lugs 25. During lowering of the casing through the fluid in the well bore, the valve element 26 will shift upwardly into engagement with the diaphragm 27, such as illustrated in FIG. 5, and will serve as a back pressure valve allowing the casing string to be floated in the well bore as the result of its lowering therewithin, the fluid in the well bore buoying or supporting a portion of the weight of the entire string of well casing. If used as a floating device, with the valve element 26 initially disposed in the lower body section 22, the diaphragm may not include its central portion 29, since the ball valve element will move back into engagement with the adjacent thicker portion of the diaphragm and transmit upwardly directed forces, due to fluid pressure, through such thicker portion and the metallic reinforcing segments 35 and the upper base portion 37 of the diaphragm to the transverse body wall 17. The elimination of the central portion 29, which is tantamount to increasing the orifice area through the diaphragm, will facilitate the downward pumping of fluids throughthe apparatus and around the ball valve element 26. For that matter, when the apparatus is to be used as a float valve device in connection with lowering a string of well casing thorugh the fluid in the well casing, a. larger diameter back pressure valve element 26 may be used, if desired, so as to engage the diaphragm at a sealing circurnference of greater diameter, one which will be capable of withstanding a still greater back pressure.

We claim:

1 In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the central portion of said elastic member being deflectable upwardly into said passage and having an orifice therethrough to allow fluid to flow upwardly through said passage at a restricted rate; reinforcing means in said elastic member outwardly of its central portion; means mounting said reinforcing means in said body for pivotal movement downwardly away from saidinwardly projecting portion; said inwardly projecting portion providing means on said body coacting with said reinforcing means to limit pivotal movement of said reinforcing means upwardly toward said passage.

2. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having afiuid passage therethrough; a plant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the central portion of said elastic member being deflectable upwardly into said passage and having an orifice therethrough to allow fluid to flow upwardly through said passage at a restricted rate; reinforcing means in said elastic member outwardly of its central portion; means on said inwardly projecting portion of tsaidbody above and coacting with said reinforcing means 'for limiting movement of said reinforcing means and that portion of said elastic member which is outwardly of said passage upwardly of said body; and means pivotally mounting the outer portion of said reinforcing means in said body to permit pivoting of the inner portion of said reinforcing means and adjacent elastic member downwardly of said body. 7

3. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a

pliant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the .central portion of said elastic member being deflectable upwardly into said passage and having an orifice therethrough to allow fluid to flow'upwardly through said passage. at a restricted rate; reinforcing means in said elastic member outwardly of its central portion and extending partially across said passage; means on said inwardly projecting portion of said body above and coacting with said reinforcing means to locate said reinforcing means in said position partially across said passage; and means pivotally mounting the outer portion of said reinforcing means in said body to permit pivoting of the inner portion of said reinforcing means and its lateral movement downwardly away from said position partially across said passage. v

4. In apparatus adapted to form part of a conduit spring to be lowered in a well bore: a body having a trans,- verse wall provided with a fluid passage therethrough; a pliant, elastic member in said body bearing against said wall and extending at least partially across said passage, the central portion of said elastic member having an orifice therethrough to allow fluid to flow through said passage at a restricted rate; reinforcing means in the outer portion of said elastic member outwardly of its central portion coasting with said wall to limit movement of said reinforcing means and outer portion of said elastic member in one direction in said body; and means pivotally mounting the outer portion of said reinforcing means in said body to permit swinging movement of said reinforcto be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body adjacent to and under said inwardly projecting portion and having an opening communicating with said passage; reinforcing means in said elastic member; means mounting said reinforcing means in said body for pivotal movement in a downward direction away from said inwardly projecting portion; and said inwardly projecting portion providing means onsaid body coacting with said reinforcing means to limit pivotal movement of said reinforcing means in an upward direction toward said inwardly projecting portion' 6. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body underand adjacent to said inwardly projecting portion and having an opening communicating with said passage; reinforcing means in said elastic member and extending partially across said passage; said inwardly projecting portion providing means on said body coacting with and above said reinforcing means to locate said reinforcing means in said position partially across said passage; and means pivotally mounting the outer portion of said reinforcing means in said a body to permit pivoting of the inner portion of said reinforcing means and its lateral movement downwardly away from said position partially across said passage.

7. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having a transverse wall provided with a fluid passage therethrough;

a pliant, elastic member in said body bearing against the a a wall adjacent to said passage and having an opening communicating with said passage; reinforcing means in said elastic member coacting with said wall to limit movement of said reinforcing means and elastic member in one direction in said body; and means pivotally mounting the outer portion of said reinforcing means in said body to permit swinging movement of said reinforcing means and elastic member away from said wall.

8. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly t I projectingportion having a fluid passage therethrough; a pliant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the central portion of said elastic member having an orifice therethrough to allow fluid to flow 7 through said passage at a restricted rate; reinforcing segments disposed circumferentially in said elastic member in its outer portion outwardly of its'central portion; means mounting said segments in said body for pivotal movement in a longitudinal direction away from said inwardly projecting portion; said inwardly projecting portion providing means on said body above said segments coacting with said segments to limit pivotal movement of said segments in a longitudinal direction toward said passage.

9. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion havinga fluid passage therethrough; a pliant, elastic member in said body-located longitudinally to one side of said inwardly projecting portion'and extending at least partially across said pas:

projecting portion of saidbody coacting with said seg ments to locate said segments in said position partially across said passage; and means pivotally mounting the outer portion of said segments in said body to permit pivoting of the inner portions of said segments and their lateral movement in a direction away from said position partially across said passage.

10. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having a transverse wall provided with a fluid passage therethrough; a pliant, elastic member in said body bearing against said wall extending at least partially across said passage, the central portion of said elastic member having an orifice therethrough to allow fluid to flow through said passage at a restricted rate; reinforcing segments disposed circumferentially in said elastic member in its outer portion outwardly of its central portion coacting with said wall to limit movement of said segments and outer portion of said elastic member in one direction in said body; and means pivotally mounting the outer portion of said reinforcingsegments in said body to permit swinging movement of said segments and outer portion of said elastic member away from said wall.

11. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body adjacent to and to one side of said inwardly projecting portion and having a central opening communicating with'said passage; reinforcing segments disposed circumferentially in said elastic member; means mounting said segments in said body for pivotal movement in one longitudinal direction away from said passage; and means on said inwardly projecting portion of said body coacting with said segments to limit pivotal movement of said segments in a longitudinal direction toward said passage.

12. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an in- ,wardly projecting portion having a fluid passage there-- through; a pliant, elastic member in said body adjacent to and longitudinally to one side of said inwardly projecting portion and having a central opening communicating with said passage; reinforcing segments disposed circumferentially in said elastic member and extending partially across said passage; means on said inwardly projecting portion of said body coacting with said segments to locate said segments in said position partially across said passage; and means pivotally mounting the outer portion of said segments in said body to permit pivoting of the inner portion of said reinforcing segments and their lateral movement in a direction away from said position partially across said passage.

13. In apparatus adapted to form part of a conduit stringto be lowered in a well bore: a body having a transverse wall providedwith a fluid passage therethrough; a pliant, elastic member in said body bearing against said wall and having a central opening communicating with said passage; reinforcing segments disposed circumferentially in said elastic member and coacting with said wall to limit movement of said segments and elastic member in one direction, in said body; and means pivotally mounting the outer portions of said segments in said body to permit swinging movement of said segments and elastic member away from said wall.

14. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the central portion .of said elastic member having an orifice therethrough to allow fluid to flow upwardly through said passage at a restricted rate; reinforcing means in said elastic member outwardly of its central portion; means on said inwardly projecting portion of said body above and coacting with said reinforcing means for limiting movement of said reinforcing means and that portion of said elastic member which is outwardly of said passage in a direction upwardly of said body; means pivotally mounting the outer portion of said reinforcing means in said body to permit pivoting of the inner portion of said reinforcing means and adjacent elastic member downwardly of said body; and a valve member movable downwardly through the tubular string, passage, orifice and reinforcing means into said body below said elastic member, whereupon said valve member can move upwardly into engagement with said elastic member to close said orifice and passage.

15. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having an inwardly projecting portion having a fluid passage therethrough; a pliant, elastic member in said body under said inwardly projecting portion and extending at least partially across said passage, the central portion of said elastic member having an orifice therethrough to allow fluid to flow through said passage at a restricted rate; reinforcing means in said elastic member outwardly of its central portion and extending partially across said passage; means on said inwardly projecting portion of said body coacting with said reinforcing means limiting movement of said reinforcing means and that portion of said elastic member which is outwardly of said passage upwardly of said body; means pivotally mounting the outer portion of said reinforcing means in said body to permit pivoting of the inner portion of said reinforcing means and adjacent elastic member downwardly of said body and lateral movement of said inner portion of said reinforcing means in a direction away from said position partially across said passage; and a valve member movable downwardly through the tubular string, passage, orifice and reinforcing means into said body and below said elastic member, whereupon said valve member can move upwardly into engagement with said elastic member to close said orifice and passage, said valve member having a diameter less than the diameter of said passage but greater than the transverse distance across said reinforcing means when located partially across said passage.

16. In apparatus adapted to form part of a conduit string to be lowered in a well bore: a body having a transverse wall provided with a fluid passage therethrough; a pliant, elastic member in said body bearing against said wall extending at least partially across said passage, the central portion of said elastic member having an orifice'therethrough to allow fluid to flow through said passage at a restricted rate; reinforcing segments disposed circumferentiallyin said elastic member in its outer portion outwardly of its central portion coacting with said Wall to limit movement of said segments and outer portion of said elastic member in one direction in said body; means pivotally mounting the outer portion of said reinforcing segments in said body to permit swinging movement of said segments and outer portion of said elastic member away from said wall; and a valve member movable downwardly through the tubular string, body passage, orifice and reinforcing means into said body below said elastic member, whereupon said valve member can move upwardly into engagement with said elastic member to close said orifice and passage with said elastic member bearing against said wall.

References Cited in the file of this patent UNITED STATES PATENTS 2,743,905 Eckel May 1, 1956 2,829,719 Clark -r Apr. 8, 1958 3,072,145 Nelson Ian. 8, 1963 

5. IN APPARATUS ADAPTED TO FORM PART OF A CONDUIT STRING TO BE LOWERED IN A WELL BORE: A BODY HAVING AN INWARDLY PROJECTING PORTION HAVING A FLUID PASSAGE THERETHROUGH; A PLIANT, ELASTIC MEMBER IN SAID BODY ADJACENT TO AND UNDER SAID INWARDLY PROJECTING PORTION AND HAVING AN OPENING COMMUNICATING WITH SAID PASSAGE; REINFORCING MEANS IN SAID ELASTIC MEMBER; MEANS MOUNTING SAID REINFORCING MEANS IN SAID BODY FOR PIVOTAL MOVEMENT IN A DOWNWARD DIRECTION AWAY FROM SAID INWARDLY PROJECTING PORTION; AND SAID INWARDLY PROJECTING PORTION PROVIDING MEANS ON SAID BODY COACTING WITH SAID REINFORCING MEANS TO LIMIT PIVOTAL MOVEMENT OF SAID REINFORCING MEANS IN AN UPWARD DIRECTION TOWARD SAID INWARDLY PROJECTING PORTION. 